Temperature control technology has been developed for machinery since the dawn of the industrial era. Air cooling, liquid cooling, and more exotic techniques such as thermo-electric cooling have long been known and applied to machines such as engines, hydraulics, pneumatics, industrial processing machines, electronics, and all manner of other types of mechanical and electrical equipment. In addition to cooling, temperature control technology can be applied to increase temperatures of machinery and systems for various purposes. The operating conditions expected to be encountered, and in particular duty cycle and ambient environment, commonly drive the selection of appropriate temperature control techniques and equipment. Many persons will be familiar with radiators, water pumps, oil pumps, oil coolers, and other equipment used in connection with common machinery such as engines, automobiles, and even certain tools and electrical equipment.
In many instances, the temperature control requirements of a piece of equipment, for example an off-highway or underground mining machine, can vary substantially depending upon what part of the machine is of interest for temperature control. In some instances, an integrated cooling system that pumps a liquid coolant past multiple different thermal loads can sufficiently cool (or heat) the subject items without any necessity for independently controlling the temperature of each. By way of example, certain engine system designs are known where an internal combustion engine and an oil cooler for oil used in the engine or other parts of the machine are cooled by conveying a liquid coolant in series past the engine block as well as the engine oil cooler. A heat exchanger for heating an operator compartment can also be placed in the fluid series loop. While each separate thermal load may be sufficiently cooled, in some instances such techniques are not optimally efficient, as one or more of the thermal loads might be cooled further than it needs to be, or another cooled less than optimally.
U.S. Pat. No. 8,336,319 B2 to Johnston et al. is directed to a thermal management system with Dual Mode Coolant Loops. In Johnston et al., the system proposed includes a first coolant loop in thermal communication with a battery system, a second coolant loop in thermal communication with a drive train component, and a valve system that apparently enables a first mode where the coolant loops are in parallel and a second mode where the coolant loops are in series. While Johnston et al. may provide advantages for certain applications, there is ample room for improvement in the temperature control field.